Value Collection MSC-04489563 Straight Flute Tap 1-3/8-12 Unf

Product Description

The VALUE COLLECTION MSC-04489563 is a straight flute bottoming tap designed for cutting internal threads in through-holes and blind holes where the thread must extend close to the bottom. Ground to a 3B class of fit with an H4 thread limit, it produces accurate 1-3/8-12 UNF right-hand threads suitable for precision fastener applications. The tool is manufactured from high-speed steel with a bright, uncoated finish. With 6 flutes, it provides good chip clearance and cutting stability in a range of workpiece materials. Thread length is 1.5 inches and overall length is 6-1/16 inches. Machinists and toolroom technicians typically install this tap in CNC machining centers, engine lathes, or manual tapping fixtures.

This bottoming tap is suited for applications where a standard or plug tap has already started the thread and full thread depth to the bottom of a blind hole is required. It is commonly used in mechanical, industrial maintenance, and fabrication environments. The 1-3/8-12 UNF thread form is a fine-pitch unified thread, making this tap a typical choice for bolted joints that require greater tensile strength or finer adjustment than coarse-thread counterparts. No coolant-through capability is present, so external coolant or cutting fluid should be applied during use.

Key Features

• 1-3/8-12 UNF right-hand thread form for fine-pitch unified internal threading
• Bottoming chamfer allows threading to the bottom of blind holes
• 6 straight flutes for cutting stability and chip clearance
• H4 thread limit with 3B class of fit for consistent dimensional accuracy
• High-speed steel construction for general-purpose tapping across a broad range of materials
• Bright, uncoated finish — no coating buildup to affect thread tolerance

Compatibility

Designed as an OEM-style replacement or direct-use bottoming tap for standard tapping chucks, CNC rigid-tapping holders, and manual tapping fixtures that accept straight-shank taps in the 1-3/8-12 UNF size range.

Installation Notes

This tap should be installed by a qualified machinist or toolroom technician using a properly sized tap holder or tapping chuck rated for the shank diameter. Always ensure the workpiece is securely fixtured and the spindle is aligned perpendicular to the hole axis before beginning the tapping operation. Apply a suitable cutting fluid or tapping compound throughout the operation to extend tool life and improve thread finish. For blind-hole applications, verify hole depth is sufficient to accommodate the chamfer length before attempting to reach full thread depth.